Left axis deviation as a single screening criterion in acquired nonvalvulvar heart disease. Association with abnormal systolic time intervals in hypertensive subjects.

The value of left axis deviation (LAD) as a single discriminator of clinical cardiac abnormality and its association with reduced left ventricular function was investigated in 100 consecutive ambulatory subjects with LAD, and 100 age and sex-matched subjects without LAD from the patient population of a voluntary screening clinic. Analysis of clinical data and measurement of QRS frontal plane axis as well as systolic time intervals (STI) were each done separately by different investigators in a blind manner. The only large groups in the study population were those with coronary heart disease and those with hypertension. The high prevalence of definite and probable coronary artery disease among subjects with LAD (32/100) contrasted with its paucity in the control group (8/100). Hypertensive and borderline hypertensive subjects occurred in sufficient numbers.